The present invention relates to a brake system which is capable of self-adjustment during vehicle operation.
Vehicles employ a number of brake systems including mechanical and hydraulic brakes. For example, some currently available snowmobiles contain hydraulic brakes and other models use mechanical brakes. Some snowmobile manufacturers recommend that a snowmobile brake system including the brake lever, brake lever travel, wear indicator or jam nut clearance, cable, caliper, spring and disk be checked daily for wear or damage, smooth operation, and proper adjustment.
To better understand what is involved in adjusting a mechanical brake system today, take a brief look at the mechanical brake system used today such as a Nipon GT brake system. A GT brake system has a housing bracket for securing a caliper assembly, a pair of spacers, and a mounting bracket. The caliper assembly includes a caliper and brake pad on one side of a disk brake. A caliper half assembly pad spring and a brake pad are on the other side of the disk brake. Attached to the caliper half assembly is a spring, cotter pin, clevis and clevis pin.
Two specific examples of snowmobile brake system service items which should be checked frequently and serviced as required are the brake pad wear check and the brake lever travel check. Brake pad wear is monitored by checking the gap maintained between the wear indicator and the lock nut mounted on the brake adjusting bolt. Extending in sequence outwardly from the caliper half assembly in the direction opposite of the disk brake is the brake arm with the one end fixed to the clevis and the other end integrally connected to a thread which screws into the caliper half assembly. Adjacent to the brake arm is a locking tab which has one tab bent over the brake arm. Next to the jam nut is a gap which is limited on the right side of the gap by a wear indicator collar. An adjusting bolt extends through the wear indicator lock nut, locking tab, brake actuator arm and beyond the brake actuator thread within the caliper half assembly. Take note of the gap between the lock nut and the wear indicator. When the brake pads are new, the gap normally will be slight. Later, after significant vehicle and brake use, the gap increases and the wear indicator will bottom out against the lock nut when the nut is tightened. When the wear indicator bottoms out, it indicates that the brake pads are worn and must be replaced. Inspecting the gap size is also important when adjusting the brake lever travel.
To check brake lever travel, first open the hood. Rotate the brake disk by hand while at the same time applying the brake lever. Continue until the brake is locked. When the brake is locked, measure the distance between the handle bar brake lever and the lever stop located next to the steering handles on the snowmobile. The distance should be a predetermined amount. If the distance measurement is incorrect, then the brake lever travel must be adjusted. Specifically, if the handle bar brake lever to the lever stop distance is less than predetermined distance, then adjust the brake lever travel by prying the lock washer tab away from the adjusting bolt lock nut. Loosen the lock nut then turn the adjusting bolt counter-clockwise to loosen until the brake lever travel is correct. Alternatively, if brake lever travel exceeds a predetermined distance, then adjust the brake lever travel by prying the locked washer tab away from the adjusting bolt lock nut. Loosen the lock nut. Then turn the adjusting bolt clockwise to tighten until the brake lever travel is correct. Once the brake lever travel is correct, tighten the lock nut against the brake actuator arm and bend the lock washer tab over the lock nut to lock it. If the wear indicator bottoms out against the lock nut when performing this procedure, the brake pads are worn and require replacement. Check the brake before starting the engine. If the brake does not lock when the brake lever is compressed, do not start the engine until the brake is repaired or adjusted properly. Finally, close and secure the hood.
Snowmobile users who are unsure about the preceding procedure for brake alignment or who find brake alignment difficult are recommended to refer their brake alignment to their snowmobile dealer or qualified snowmobile mechanic. Other concerns involved with improper adjustment of mechanical brakes in vehicles can be found in cars, trucks, all-terrain vehicles. For the foregoing reasons, there is a need for a mechanical brake system that is self-adjusting and that can be adjusted to within a small tolerance as needed.
Accordingly, it is the object of the present invention to provide an infinitely self-adjusting mechanical brake system that improves upon or overcomes the disadvantages of the currently used systems.